Wire forming machine



Aug. 16, 1955 H. H- FANTE ET AL WIRE FORMING MACHINE 4 Sheets-Sheet lFiled Jan. 50, 1952 EIL Aug 16, 1955 H. H. FANTE ET AL WIRE FORMINGMACHINE 4 Sheets-Sheet 2 Filed Jan. 30, 1952 Aug. 16, 1955 H. H. FANTEET Al.

WIRE FORMING MACHINE 4 SheetS-Sheet 3 Filed Jan. 50, 1952 Auga 16, 1955H. H. FANTE ET A1. 2,715,424

WIRE FORMING MACHINE Filed Jan. 30, 1952 4 Sheets-Sheet 4 INVENTORS WIREFont/into MACHINE Harry H. Fante, Riverside, Mitchell J. Shepard,Cicero, and August T. Gona, Berwyn, Ill., assignors, by mesneassignments, to Rockwell Spring and Axle C ompany, Coraopolis, Pa., acorporation of Pennsylvania Application January 30, 1952, Serial No.269,044

12 Claims. (Cl. 140-71) This invention relates to improvements in wirebending machines and particularly to an improved machme for bendingpreformed corrugated or zigzag wire. g

Corrugated or zigzag wire has been used extensively as spring supportsfor seats and backs of seats and particularly in the seat constructionsof motor vehicles. Such zigzag wire is shaped by laterally bending astraight length of wire rst on one side then the other side thereof andresults in a formation wherein the wire exhibits alternate oppositelydisposed wire loop sections. connected together by transverselyextending wire sections. As it is made, the corrugated wire is cut olfinto strips of desired length and usually a curvature is set into thestrip which causes the strip to assume an arched formation from one endto the other end thereof.

The present invention concerns an improved machine for further shapingzigzag wire and particularly for bending or folding strips of such wireat one or more places to extend portions of the strips at angles to thebalance of the strips. This is effected by twisting one or more loopconnecting transverse sections of a zigzag W1re strlp about theirrespective axes. In the past, it has been the practice to change theshape of wire products by twistmg certain portions thereof upon theiraxes. Hand operated devices have been used for this purpose andparticularly for twisting laterally bent portions of strut wires and thelike for the purpose of producing the desired bend 1n the wire. Thepresent invention constitutes an improvement over such hand operateddevices and incorporates power means for effecting the twistingoperation and for timing the movements of the parts to accomplish thisend.

An important object of the invention is to provide an improved machinefor rapidly bending zigzag wire into the desired formations andparticularly for impartlng folds therein which causes the zigzag wire toassume certain angular formations. Another important object of theinvention is to provide an improved machine of this character andcomprising parts which may be fabricated and assembled at low cost andwhich are arranged in a distinctly novel relation to one another and forquickly engaging the zigzag wire and for accurately and rapidlyproducing the desired bent formation. A further 1mportant object of theinvention is to provide an improved machine of this character which isarranged in a novel manner for the convenience of the operator and whichprovides a work table for stacking unbent and bent zigzag wire stripsadjacent to the operating members for elfecting the bending operation.

Various other objects, advantages and meritorious features will becomemore fully apparent from the following specification, appended claimsand accompanying drawings wherein:

Fig. l is a side elevation of a machine embodying the invention;

Fig. 2 is a plan view of the machine illustrated in Fig. 1;

Fig. 3 is a vertical sectional view of the upper portion ot the machinetaken along line 3-3 of Fig. 2 and shownited States Patent 2,715,424`Patented Aug. 16, 1955 ing the manner of supporting a portion of azigzag wire thereon;

Fig. 4 is a side elevation of the upper portion of `the machine showingin dotted lines the position assumed by a zigzag wire prior to thebending thereof;

Fig. 5 is an enlarged plan view of a portion of the table andillustrating by full and dotted lines the positlons of two of theoperating members at the commencement and termination of a wire bendingoperation;

Fig. 6 is a fragmentary vertical sectional view taken along line 6-6 ofFig. 2;

Fig. 7 is a horizontal sectional view taken along line 7-7 of Fig. 4;

Fig. 8 is a plan view of a foot controlled valve for controlling theoperation of the hydraulic motors; and

Fig. 9 is a side elevation of the foot controlled valve of Fig. 8.

In the illustrated embodiment of the invention, the operating parts aresupported upon a suitable frame which may consist of upright members orlegs 10 having floor engaging inserts 12 in the lower ends thereof. Thelegs 1t) may be connected together intermediate their heights by crossframe members 14 which are welded or otherwise secured to the uprightmembers. The upper ends of the legs terminate on the same horizontallevel, and overlying or capping these ends is a base platform or table16. The platform is provided with downwardly projecting marginal flanges13 which embrace the upper portions of the legs and enclose the.` sametherewithin.

The machine is provided with a wire support or work table 26 which asshown in Figs. l to 4 is supported in vertical spaced relation to theplatform 16. Preferably the Work table is a metallic sheet having a atupper surface of relatively large expanse as compared with the areaoccupied by the wire engaging operating members of the machine. Thislarge expanse enables an operator of the machine to form separate groupsof unbent and bent zigzag wire strips thereon in spaced relation to thewire bending members but within arms reach. The work table is providedin one convenient area to the operator with a relatively small opening22 therethrough. The opening may be of the rectangular formation shownin Fig. 2. Forming a small cluster above and immediately adjacent to theopening are the wire engaging and bending members of the machine.

Between the wire support or worlt table 26 and the base platform 16 is astructure including supporting plates and operating mechanism forcontrolling the movements of the wire engaging and bending members. Thestructure serves to support the work table in spaced relation to theplatform. Two superimposing plates constitute the primary supportingparts of the structure. One plate is indicated at 24 and is referred toas the base plate. The other plate superimposes the base plate and isindicated at 26. The two plates may be metal castings and of the crosssectional formation shown in Fig, 3. The base plate is provided with anintermediate horizontal portion 2S which is recessed both from its upperand lower edges and cooperates with the upper plate 26 to form ahorizontal passage through which certain parts of the drive mechanismextend as hereinafter described. The upper plate is provided withupwardly extending parallel side anges 30-30 which form rests for thework table. Between these anges, the upper plate is provided with anupwardly projecting vertically bored body 32 which is aligned with theopening 22 in the work table.

Movably supported in the bore of the body portion 32 of the upper plate26 and located above the upper surface of the work table are the wireengaging and bending members of the machine. One of these members servesas a rest for one loop section of a zigzag ICE wire strip and isstationary during the wire bending operation. Either one or twosimilarly formed rotatable members are employed to engage the zigzagwire strip and upon rotation bend a portion of the wire strip relativeto the balance. ln the illustrated embodiment of the invention two suchrotary members are shown but it is understood that either one or theother may be omitted to vary the type of bend formed in the zigzag wire.

The normally stationary wire engaging member is in the form of acylindrical shaped rest pin 34 supported as shown in Fig. l in spacedrelation to the upper surface of the work table and having its axisextending horizontal and parallel to the plane of the work table. Oneend of the rest pin is reduced as shown at 36 in Fig. 6 and is fittedinto and secured to the upper end of a vertical member, post, or shaft38. The rest pin is preferably provided with a peripheral recess orgroove 40 which as shown in Figs. 3 and 4 functions as a seat forretaining the loop section of the wire against axial movementtherealong. The groove 4t) is preferably located near the outer end ofthe rest pin and is of such a depth and width as to substantially fullyseat the wire loop section therewithin. In this manner the rest pinServes as a saddle for a downwardly opening loop section of zigzag wirereceived thereon. Preferably the rest pin is located at a height abovethe table Ztl such that when a loop is fully seated thereon the balanceof the zigzag wire will lightly bear upon the upper surface of the tableas is evident in Fig. 4.

Located above the work table but below the level of the rest pin are theone or two rotatable wire engaging members previously referred. Two suchmembers are herein shown and since they are similarly constructed theyare referred to by the same reference characters. Each rotatable membercomprises a head portion 42. located above the level of the work tableand over the opening 22 thereof. Each member is further provided with avertical stem portion 44 which enters a bore in the upper end of a shaft46. A bolt 48 entering the lower end of the shaft is utilized forsecuring the stem portion of each member to its respective shaft. Eachhead 42 may be elongated in one dimension as shown in Fig. 5. Providedin each head is an upwardly opening recess or groove 50 which as shownin Fig. 5 is preferably located on the axis of the long dimension of thehead. The recess or groove t] of each head is of a width sutlicient toslidably receive a loop section of a zigzag wire strip and of a depthsuch that its bottom extends substantially flush with the upper surfaceof the work table as illustrated in Fig. 3.

The two shafts 46-46 for the heads 4lZ-LZ are located side by side andunder the outer end of the rest pin. The two shafts are journaled in thebody portion 32 of the upper plate 26 for rotation about theirrespective axes and for this purpose a separate brushing 52 is providedin the body portion of each shaft. lt is preferred to additionallysupport the shafts 45s- 45 in the base plate 24, and for this purposethe intermediate portion 28 of the base plate is provided with a boreco-axially aligned with the bore in the upper plate. The lower ends ofthe two shafts 46-46 extend into the bore of the base plate and aresuitably journaled therein by means of bushings 54-54. The bolts 4Ssecurely hold the heads 42 on their respective shafts for joint rotationtherewith.

The two shafts 46-46 are mounted so that the axes of rotation thereofand the heads 4.2 42 extend upwardly past the opposite sides of the restpin 3/-5 and substantially tangential to the peripheral surface thereof.The two shaft axes are disposed in the plane of the peripheral groove 40but on opposite sides of the rest pin. The heads 42-42 are preferablyeccentrically mounted on their respective shafts and arranged so that inthe starting position of the parts their slots 5t) substantially alignwith the s ist;

peripheral groove 40. The initial or starting position of the heads isshown in Fig. 2 and in full line in Fig. 5. The slight angular relationof the slots 5S0 to the groove 40 in exhibited in Fig. 2 is toaccommodate a preset arch existing in the zigzag wire strip. Thisangular relation may be varied or the slots brought into exact alignmentwith the plane of the groove 40 depending upon whether an arch is presetinto the zigzag strip and its radius of curvature.

It is apparent from the description thus far that for operating upon azigzag wire strip, such as generally indicated at 56 in Figs. 3, 4 and5, the strip is positioned so that it extends edgewise to the uppersurface of the working table and in a plane perpendicular to the axis ofthe rest pin. Such a zigzag wire strip comprises alternate upper andlower loop sections 5S and 60 respectively connected together bytransverse wire sections 62. The strip is manually positioned in thegrooves of the rest pin 34 and the heads -42-42 with a selected upperloop section Sti in straddling relation to the rest pin and seated inthe groove 4t) thereof. rlhe two immediately adjacent lower loopsections dit-6i) are received in the upwardly opening grooves of theheads 42-42. The two transverse wire sections 62-62 connecting the upperseated loop 58 with the two adjacent lower loops 60-60 extendvertically. Since the pin supported loop 58 is fully seated in thegroove til the two transverse wire sections 62--62 leading downwardlytherefrom are disposed in substantially but not necessarily accuratealignment with the rotating axes of the heads 42 and the shafts 46. Whenboth shafts and their respective heads are rotated, such as to thedotted positions shown in Fig. 5, the transverse wire sections 62-62connected to the seated loop 58 are twisted about their respective axes,thus imparting two closely adjacent folds or bends in the zigzag wire atthe locations of these transverse sections.

When two such rotary heads L32,--42 are employed as in the illustratedembodiment of the invention, they are preferably simultaneously rotatedabout their respective shaft axes and in directions opposite to oneanother. This is effected by the provision of drive mechanism operatingin the passage formed between the intermediate portion 23 of the baseplate and the upper plate 26. As best shown in Fig. '7, this mechanismpreferably comprises two reciprocating rack bars tdsl-ifiof similarconstruction, one for each shaft e6. Carried by each shaft 'i6 is apinion 66, the teeth of which are cngageable with the teeth 68 of therack bar with which the shaft is associated. The two raclf. bars areguided for travel along separate converging paths by two oppositelydisposed wedge-shaped members ofinii which rest upon the hori zontalportion 255 of the base plate 24 as shown in Fig. 3.

The rack bars 6-4--64 are preferably reciprocated by hydraulic means andsuch means employing a, compressible huid. As shown in Fig. 2, each rackbar is connected by means of a tie rod 'itt to the exterior end of apiston rod '72. Each piston rod 77. extends into a cylinder '7d andcarries on its inner end a piston head '76. Compressible uid, such asair, is introduced under pressure into the cylinders alternately onopposite sides of the piston head '7n to reciprocate the same and therack bars associated therewith.

Adjustable stops are provided for limiting the extent of travel of the'two rack bars 64-64 As shown in Figs. 2 and 7 the front side of thesuperimposing plates Z4 and 26 are closed by a plate 7S forming a sidewall therefor. Carried by the wall 73 are two adjustable stop members8%! 80 which are disposed in line with the travel of the rack bars andare adapted to be engaged thereby. Each stop member Sil may be a setscrew held in any adjusted position relative to the wall 78 by means ofa jam nut 82. Each rack bar 64 may carry a replaceable wear resistingelement in the form of a headed bolt S4 which is engageable with theinner end of the adjacent stop member 80, By axially adjusting the stops80, the distance of travel of the two rack bars 64--64 may be varied andin this manner the amount of rotation: of the heads 42;-42 may beregulated.

The two pistons 76-76 are reciprocated in their respective cylinders'74-74 by means of fluid pressure directed into the opposite ends of thecylinders. As shown in Fig. 2, each cylinder is provided with a fitting86 at one end and a fitting 8S at the other end which serve to connectconduits leading to` a source of compressible uid pressure (not shown).The conduits leading to the outer end fittings of the two cylinders areindicated by the reference character 90; the conduits leading to theinner end fittings 88 of the two cylinders are indicated at 92. Theseconduits are connected through a valve with a source of pressure. Thevalve is generally indicated at 94 in Figs. 8, 9 and l0 and is suitablydesigned to alternately direct the fluid under pressure through eitherthe conduits 90 or the conduits 92 to reciprocate the pistons in theirrespective cylinders.

The valve 94 for controlling the flow of fluid pressure is preferablyfoot controlled and located under the` machine near the floor so that itmay be actuated by the foot of the operator. The valve is provided witha pedal or foot lever 96 which is secured to the outer end of a rotaryvalve member 98. The latter extends into the body of the valve and isported so that it directs' fluid to either one or the other ends of thecylinders depending upon the position of the pedal. The two conduits90-90' for the outer ends of the cylinders are joined together into acommon conduit 100 leading to one side of the valve. Similarly, theconduits 92-92 for the inner ends of the cylinders are joined togetherand enter the valve through a common conduit 102. Fluid pressure, suchas air under pressure, is directed into the valve body by means of aconduit 104 which is shown in Figs. 8 and 9 and may be located betweenthe two conduits 100 and 102.

A coiled spring 1% encircles a tubular portion of the valve body throughwhich the member 98 extends and is fixed at one end to the valve bodyand at the other end tothe foot pedal. The spring is so mounted that ityieldingly urges the pedal to its upper position shown in Fig. 9. Inthis position, the ports ot' the valve are so arranged as to directiluid pressure to the inner or forward ends of the cylinders 74-7d.However, when the pedal 96 is depressed against the resistance of thespring 106 the ports in the valve body are arranged to direct fluidpressure to the outer or rear ends of the cylinders 74-74. Thus,

when the pedal is depressed, fluid is directed into the r cylinders tourge their respective pistons outwardly therefrom to advance the rackbars toward their respective limit stops and to rotate the heads 42-42in the direction to impart the desired bend to the zigzag wire sectionbeing operated upon.

The rest pin supporting post 38 is movable axially through the table. ltis reciprocated upwardly at the conclusion of each wire bendingoperation in order to clear the zigzag wire sections out of the heads42-42 before their return to their initial starting position. In theillustrated embodiment of the invention, this is accomplished by powermeans comprising a solenoid 108 which is suspended from the base plate24 by studs 109 and surrounds an armature 110 of magnetically attractable material. The armature constitutes a lower sec tional portionof the post 38 and the two are secured together for joint reciprocationby a threaded connection indicated at 112. The armature is so related tothe solenoid that when the latter is energized it will cause thearmature to be raised and lift the post and the rest pin 34 associatedtherewith.

Upward movement of the post 38 is yieldingly resisted by means of acoiled spring 114 surrounding the lower end of the post as shown in Fig.6. The upper end of lil the coiled spring is seated against the bushing54 mounted inl the base plate 24 and the lower end is seated upon a capor nut 116 surrounding the upper end of the armature. The post 38 isheld from rotation by means of a key 118 xed to the upper plate 26 andentering a longitudinal groove 120 formed in the side of the post.

The solenoid 108 is energized when the pedal 96` is depressed to itslowest position. This is accomplished by the closing of the solenoidcircuit when the pedal is moved to such position. As shown in Figs. 8and 9, the valve base carries a limit switch 122 from which projects adepressible electrical contact member 124. When depressed, the contactmember closes the circuit 126 extending to the solenoid 108. Thedepressible contact member 124 is supported adjacent to the axis aboutwhich the pedal 96 moves and may be located on the side of the axisopposite to the pedal as shown in Fig. 9. Associated with the pedal andmovable therewith is a body 128 carrying a trigger finger 130 which,when the pedal approaches a fully depressed position, engages thecontact member 124 and depresses the same to close the solenoid circuit.

It is thus evident that during the early depressible movement of thepedal fluid pressure is directed to the rear or outer ends of the aircylinders: to move the rack bars and the heads 42-42 in the direction toperform the wire bending operation, and that when the pedal is fullydepressed the solenoid circuit is closed and the post 38` and itsassociated rest pin 34 are raised to clear the zigzag spring section outof the heads. When foot pressure is removed from the pedal, it returnsto its initial raised position causing fluid under pressure to ow to theinner or forward ends of the cylinders to retract the back bars andreturn the heads t2--42 to their initial starting positions. At the sametime, the upward movement of the pedal opens the solenoid circuitthereby de-energizing the solenoids and permitting the post 38 and restpin 34 to return to their initial operating position.

What we claim is:

1. In a machine for bending pre-formed zigzag wire having alternateoppositely disposed loops each connected to one another by a transverseyextending wire section, a table, a cylindrically shaped member supportedspaced above the table and extending parallel thereto and sodimensionally proportioned as to receive a loop of a zigzag Wire andform a supporting rest therefor, a pair of members located above thetable near the first member and spaced there-below and each providedwith a slot shaped to receive an opposite next adjacent loop to the loopof zigzag Wire thus supported on the first member, said pair of membersbeing rotatably mounted and provided with drive means extending throughthe table to the underside thereof, and power means under the tableoperatively connected to said drive means and adapted to rotate the sameto impart a twist to the connecting transverse wire sections extendingbetween said loops of zigzag wire.

2. In a machine for imparting bends in preformed zigzag wire strips, atable having a flat expanse sufficient to carry a plurality of preformedzigzag wire sections, mec-Huisnr located above the table for bending azigzag wire strip and occupying a small portion of the entire surfacearea of the table, said mechanism including two members for engaging twoimmediately adjacent but oppositely disposed loop portions of a zigzagwire strip, one of said members constituting a horizontal extendingcylindrically shaped pin positioned in spaced relation to the surface ofthe table and being dimensionally proportioned to function as a rest fora loop portion of a zigzag wire strip received thereon, said memberbeing supported above the table for vertical. reciprocation toward andaway from the table, the other member constituting a vertical `shaftprovided with an upwardly opening transverse slot on the upper endthereof shaped to receive an opposite loop portion of the zigzag wirestrip next adjacent to the loop portion received on the first member,said shaft extending through the table to the underside thereof, anddrive means under the table operatively coupled to the shaft forrotating the same.

3. In a machine for imparting bends in preformed zigzag wire strips, atable having a flat expanse sutlicient to carry a plurality of preformedzigzag wire sections, mechanism located above the table for bending azigzag wire strip and occupying a small portion of the entire surfacearea of the table, said mechanism including three members for engagingthree immediately adjacent but alternately oppositely disposed loopportions of a zigzag wire strip, one of said members constituting ahorizontal extending cylindrically shaped pin positioned in spacedrelation to the upper surface of the table and being dimensionallyproportioned to function as a rest for a downwardly opening loop portionof a zigzag wire strip received thereon, the remaining two membersconstituting a pair of vertical shafts having their upper endsterminating below the rest pin and on opposite sides thereof, the upperends of said shafts being each provided with a transverse slot shaped toreceive and support the upwardly opening loop portions on either side ofthe loop portion resting on the pin, said shafts extending through thetable to the underside thereof, and drive means under the tableoperatively coupled to the shafts and arranged to rotate the same indirections counter to one another.

4. A machine for bending preformed zigzag wire comprising, incombination, a substantially cylindrically shaped member adapted toenter one of the loops of a zigzag wire and serve as a rest therefor, apair of members rotatably mounted one on each side and adjacent to thefirst member and shaped to engage the next successive but opposite loopsto that of the loop of the zigzag wire resting on said first member, theaxes of rotation of said pair of members extending substantiallytangential to the first member, means for rotating said rotatablemembers to twist the transverse section of wire connecting said adjacentloops t0 impart a bend in the zigzag wire, means for providing bodilyshiftable movement of the cylindrically shaped member toward and awayfrom the other members to lift a zigzag wire resting on the cylindricalmember away from and out of engagement with the other members, and meansfor moving the bodily .shiftable member away from the other ,I membersimmediately following the wire twisting operation.

5. In a machine for bending preformed zigzag wire having alternateoppositely disposed loops each connected to one another by a transversesection of wire, a substantially cylindrically shaped member of a sizeto receive one of the loops of a zigzag wire and serve as a resttherefor, said member having a peripheral groove into which the loopthus received may seat to hold the loop against axial shiftable movementrelative to the member, a pair of members having slots shaped to receiveand overlap upon the opposite sides of loops of a zigzag wire, meansmounting said pair of members for rotation adjacent to the first memberand such that the slots thereof open toward the first member and arearranged to receive and overlap the opposite and next succeeding loop ofthe zigzag wire thus resting on the first member, means for rotating thepair of members to twist the transverse sections of wire connecting saidloops about their axes to impart a bend to the zigzag wire, meansmounting the first member for bodily shiftable movement toward and awayfrom the pair of members, and means for bodily shifting the first memberimmediately following the twisting operation performed by the pair ofmembers.

6. A machine for bending pre-formed zigzag wire comprising, incombination: a table, a post projecting upwardly through the table andmovable axially through the table, a cylindrically shaped member mountedon the post and extending parallel to the table and located spaced abovethe table and adapted to support a downwardly opening loop of a zigzagwire, a pair of wire twisting heads projecting above the plane of thetable spaced below the member and disposed on opposite sides thereofadjacent the post and adapted to engage the loops of wire adjacent andon opposite sides of the loop received over the member, means coupledwith the heads to rotate the same to bend the Wire around axes extendingparallel to the post, and means coupled with the post to reciprocate thesame and move the cylindrically shaped member toward and away from thetable to lift a zigzag wire resting upon the cylindrical member andengaged with the heads upwardly away from the heads and to a position ofdisengagement with the heads.

7. A machine for bending pre-formed zigzag wire comprising, incombination: a table, a post projecting upwardly through the table andmovable axially through the table, a cylindrically shaped member mountedon the post and extending parallel to the table and located spaced abovethe table, said member exhibiting a wire-receiving groove adapted toreceive the curved portion of a downwardly opening loop of a zig-zagwire to support the wire on the member with the sides of the grooveoverlying the wire loop, a pair of slotted wire twisting heads projectedabove the plane of the table spaced below the member and disposed onopposite sides thereof with the slots in the heads alignable with thegroove in the cylindrical member, said slots adapted to receive theloops of wire immediately adjacent and on opposite sides of the loopreceived within the groove in the cylindrically shaped member, meanscoupled with the heads to rotate the same in opposite directions, andmeans coupled with the post to reciprocate the same and move thecylindrically shaped member toward and away from the table a distanceexceeding the depth of the slots in the wire twisting heads to lift azigzag wire resting in the groove of the cylindrical member and receivein the slots of the heads upwardly away from the heads and out of theslots thereof.

8. In a machine for imparting bends in preformed zigzag wire strips, atable having a flat expanse sufficient to carry a plurality of preformedzigzag wire sections, mechanism located above the table for bending azigzag wire strip and occupying a small portion of the entire surfacearea of the table, said mechanism including three members for engagingthree immediately adjacent but alternately oppositely disposed loopportions of a zigzag wire strip, one of said members constituting ahorizontally extending rest pin positioned in spaced relation to theupper surface of the table and being dimensionally proportioned tofunction as a rest for a downwardly opening loop portion of a zigzagwire strip received thereon, power means under the table for moving therest pin toward and away from the table including a reciprocable postextending through the table and supporting the pin thereon, theremaining two members constituting a pair of vertical shafts havingtheir upper ends terminating below the rest pin and on opposite sidesthereof, the upper ends of said shafts being each provided with atransverse slot shaped to receive and support the upwardly opening loopportions on either side of the loop portion resting on the pin, saidshafts extending through the table to the underside thereof, drive meansunder the table operatively coupled to the shafts and arranged to rotatethe same in directions counter to one another, and means coupled to thepower means and to the drive means an-d responsive to the movement ofthe drive means to actuate the power means to cause the pin to beshifted away from the table following the twisting of the wire and for adistance suicient to clear the loops out of the slots.

9. In a machine for bending a preformed zigzag wire having alternateoppositely disposed loops each connected to one another by atransversely extending wire section,

a table, a wire rest supported spaced above the table and extendingparallel thereto and so dimensionally proportioned as to receive a loopof a zigzag wire an-d form a supporting rest therefor, means supportingsaid rest for vertically shiftable movement toward and away from thetable, a pair of members located above the table near the rest andspaced therebelow and each provided with a slot shaped to receive anopposite next adjacent loop to the loop of zigzag Wire thus supported onthe rest, said pair of members each being mounted on the end of avertical shaft extending through the table to the underside thereof, apinion gear mounted on each shaft underneath the table, power drivenrack means operatively coupled with the pinion gears to rotate the sameto impart rotation to the slotted pair of members to twist theconnecting transverse wire secions extending between said loops ofzigzag wire.

10. The invention as deined in claim numbered 9 characterized in thatthe power-driven rack means includes a fluid pressure operating deviceand valve means for controlling the operation of the fluid pressuredevice, and the means supporting the wire rest for vertically shiftablemovement is responsive to the actuation of the valve means to shift therest away from the table a distance sufcient to clear the loops out ofthe slots following the twisting of the wire.

11. A wire bending machine for bending a strip of preformed zigzag wirecomprising: a frame; a pair of laterally spaced apart, slotted wiretwisting heads adapted to engage over the same linear side edge of astrip of zigzag wire at spaced apart intervals with each loop of twoadjacent similarly disposed loops of the wire received in the slot ofeach head; a pair of shafts mounted for rotation on the frame; meansmounted on the frame and coupled with the shafts for rotating theshafts; each of said twisting heads mounted on one of said shafts; aslotted wire engaging and positioning member disposed opposite thetwisting heads and adapted to engage the intermediate and oppositelydisposed connecting loop of the zigzag strip from the loops receivedwithin said heads and with said connecting loop seated in the slot ofthe positioning member, said Wire engaging and positioning memberadapted to position and hold said connecting loop of the wire duringbending of the wire; and means mounted on the frame and supporting saidengaging and positioning member for shiftable movement in the plane ofthe wire strip toward and away from the twisting heads whereby 10 thewire may be cleared out of the slots in the twisting heads.

12. A wire bending machine for bending a preformed zigzag Wire stripcomprising: a frame, a wire support mounted on the frame for supportingthe zigzag wire preparatory to bending the same, a pair of slotted wiretwisting heads extending through the support and adapted to engage overthat edge of the wire resting on the support with a pair of similarlydisposed adjiacent loops of the Wire received in the slots of thetwisting heads, a pair of shafts mounted on the frame for rotation, eachof said twisting heads mounted on one of the rotatable shafts, meansmounted on the frame and coupled with the shafts for rotating the same,a slotted wire engaging and positioning member disposed opposite thetwisting heads and spaced from said support and adapted to engage withinits slot the intermediate and oppositely disposed connecting loop of thezigzag wire strip from the loops received within said twisting heads,said wire engaging and positioning member adapted to hold the Wire atthe loop with which it is engaged intermediate the loops received insaid twisting heads during bending of the wire, and means mounted on theframe and supporting the wire engaging and positioning member forshiftable movement toward and away from the twisting heads and towardand away from said support whereby the zigzag wire may be celared out ofthe twisting heads.

References Cited in the tile of this patent UNITED STATES PATENTS174,609 Wright Mar. 7, 1876 487,679 Morse Dec. 6, 1892 609,011 CriggalAug. 16, 1898 734,350 McFatn'dge July 21, 1903 904,563 Rau Nov. 24, 19081,737,261 Morin Nov. 26, 1929 1,821,894 Otaka Sept. 1, 1931 2,128,620Lyons Aug. 30, 1938 2,377,829 Vaill lune 5, 1945 2,389,055 Horton Nov.13, 1945 2,450,876 Blumensaadt Oct. 12, 1948 2,615,478 Hopkes Oct. 28,1952 2,632,482 Lincoln Mar. 24, 1953 FOREIGN PATENTS 226,328 GermanySept. 29, 1910 475,733 Canada July 31, 1951

